car (partners') - Cars play a huge part in our waking lives, and they represent a variety of things. Particularly, they are representative of the ability to move around, or the power to direct your life. They symbolize your motivating desires...sex drive, ambition, sense of failure, or whatever 'drives' you to 'get somewhere in life'. Also symbolizes independence, personal choices, and freedom.

partner in the front seat - symbolizes the attitudes directing how you live your life. That your partner is in the front seat, suggests that he influences your life,...either through your permission, dependence, domination,...or even fear.

you in back seat - suggest you feel passive in your waking life, and that you are dependent on your partner. You would rather take direction, rather than give it.

outside the house - a house represents 'the self'...outside the house is a symbol your 'persona' (your social self), what others see, and also represents your face.

strange car - suggests you feel the 'intrusion' of someone else's influence within your life.

strangers - symbolize different sides or unfamiliar aspects of your unconscious personality, or a different side of your partner that you've never seen before.
That they are dark skinned suggests that these different aspects are emotional feelings of longing, and that they have been kept hidden, or secret.

talking to partner - suggests a side of you that feels the need to talk to your partner about something, a need to express what you feel and think, or standing up for what you believe, or what you feel strongly about.

stranger trying to kiss you (felt horrified) - suggests something about yourself you do not like, or accept.

partner kissed you (felt happy) - represents acceptance, sexual agreement, and unity.

shovel - represents introspection (the work of digging into your memories),..your subconscious may be feeling the need to uncover past experiences, or what you feel is 'buried'. Because you were using it as a weapon, it could suggest you want to bury something, hide it, or cover it up.

hitting them - suggests anger that has not been acknowledged during the day. If we can't fulfill the wishes, demands, or expectations of others, we feel guilty, and our unconscious often "lets off steam" by way of aggressive attacks.
Because you were attacking the strangers, suggests that you may be angry at yourself for something you said, or fear you will say.

partner was gone - suggests a fear of being alone, or abandoned.
 __  __  __  __  __  __  __  __  __  __  __

Has something upset you recently...something you've said, or wish you'd said?
Is there something about yourself that you don't want others, especially your partner, to see or find out?
Is there something about yourself that you feel self-conscious about?
Do you have a 'secret' of sorts, that if your partner knew about, you fear he would leave you?
Is there a part of you, deep down, that wants to tell your partner something, but you are afraid to?
Do you feel strongly about something, and want to say something, but fear it will ruin your relationship with your partner?

I hope this helps you out. Best of Luck!